JP4047078B2 - Liquid crystal display - Google Patents

Liquid crystal display Download PDF

Info

Publication number
JP4047078B2
JP4047078B2 JP2002175950A JP2002175950A JP4047078B2 JP 4047078 B2 JP4047078 B2 JP 4047078B2 JP 2002175950 A JP2002175950 A JP 2002175950A JP 2002175950 A JP2002175950 A JP 2002175950A JP 4047078 B2 JP4047078 B2 JP 4047078B2
Authority
JP
Japan
Prior art keywords
liquid crystal
crystal display
electrode
display device
columnar spacers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2002175950A
Other languages
Japanese (ja)
Other versions
JP2004020946A (en
Inventor
哲也 飯塚
暢子 福岡
康行 花澤
清一 佐藤
Original Assignee
東芝松下ディスプレイテクノロジー株式会社
東芝電子エンジニアリング株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 東芝松下ディスプレイテクノロジー株式会社, 東芝電子エンジニアリング株式会社 filed Critical 東芝松下ディスプレイテクノロジー株式会社
Priority to JP2002175950A priority Critical patent/JP4047078B2/en
Priority to US10/449,193 priority patent/US6888609B2/en
Priority to TW092116255A priority patent/TWI241426B/en
Priority to KR10-2003-0038654A priority patent/KR100531937B1/en
Publication of JP2004020946A publication Critical patent/JP2004020946A/en
Application granted granted Critical
Publication of JP4047078B2 publication Critical patent/JP4047078B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/133553—Reflecting elements
    • G02F1/133555—Transflectors
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/133371—Cells with varying thickness of the liquid crystal layer
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/133388—Constructional arrangements; Manufacturing methods with constructional differences between the display region and the peripheral region
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1339—Gaskets; Spacers; Sealing of cells
    • G02F1/13394—Gaskets; Spacers; Sealing of cells spacers regularly patterned on the cell subtrate, e.g. walls, pillars

Landscapes

  • Physics & Mathematics (AREA)
  • Nonlinear Science (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Liquid Crystal (AREA)

Description

【０００１】
【発明の属する技術分野】
本発明は、一つの画素内に反射表示領域と透過表示領域とを備えた液晶表示装置に関し、とくにアレイ側の基板構造に関する。
【０００２】
【従来の技術】
近年、屋外での使用を想定した液晶表示装置として、一画素内に反射表示領域（以下、反射部）と透過表示領域（以下、透過部）とを備えた半透過型液晶表示装置が多く用いられている。この半透過型液晶表示装置は、反射部は外光を、また透過部はバックライト光を光源とし、画像表示を行っている。
【０００３】
図５は、半透過型液晶表示装置の画素構造を示す概略平面図、図６は、図５のＡ領域に対応する概略断面図である。
【０００４】
ここでは、主な構成部分について説明するものとし、他の部分の構成や説明は省略する。以下、図５及び図６を参照しながら説明する。
【０００５】
アレイ基板１０は、透明なガラス基板１１で構成されており、その平面領域は表示領域３１と額縁領域３２とに区分されている。このうち、表示領域３１には、複数の信号線１２及び層間絶縁膜１３及びを介してこれらと直交する複数の走査線１４がマトリクス状に配置され、このマトリクスの各格子（画素）毎に画素スイッチ素子としての画素ＴＦＴ１５及び画素電極１６が形成されている。また、走査線１４と並行に補助容量線１７が形成されている。
【０００６】
各画素において、透過部３３は画素の中央域に、反射部３４は画素の周辺域に配置されている。画素電極１６は透過部３３ではＩＴＯ膜等により透明電極１８として構成され、反射部３４では金属膜等により反射電極１９として構成されている。透過部３３を画素の中央域に配置するのは、画素の周辺域には、信号線１２や走査線１４等の不透明配線が多く存在するため、光利用効率上、有利なためである。また、反射電極１９は反射光の視野角を広げるため、表面に凹凸が形成されている。アレイ基板１０の外側には偏光板２０、バックライト２１が配置され、内側には、その表面を覆うように、図示しない配向膜が形成されている。
【０００７】
一方、対向基板２２は、アレイ基板と同じく透明なガラス基板２３で構成されており、その表面には対向電極２４、カラーフィルタ２５等が形成され、さらにその表面を覆うように図示しない配向膜が形成されている。また対向基板２２の外側には偏光板２６が配置されている。
【０００８】
これらアレイ基板１０及び対向基板２２は、セルギャップを規定する柱状スペーサ２７により所定間隔で対向配置され、基板の周辺を囲むように形成された図示しないシール材により貼り合わされている。また、基板間には液晶層２８が注入され、内部に充填されている。
【０００９】
ところで、半透過型液晶表示装置においては、透過部３３と反射部３４とでは光が液晶層２８を通過する経路が異なる。すなわち、透過部３３ではバックライト２１からの透過光Ｌ１が１回だけ液晶層２８を通過するのに対し、反射部３４では対向基板２２側から入射した外光が液晶層２８を通過した後、反射電極１９で反射して再び液晶層２８を通過し、反射光Ｌ２として取り出される。このため、反射光Ｌ２の方が透過光Ｌ１よりも液晶層２８を通過する距離が長くなる。したがって、反射表示時と透過表示時の両方で最適な光学特性を得るためには、反射部３３と透過部３４のそれぞれを最適なセルギャップで設計する必要がある。そこで、図６に示すように、反射電極１９の下層に樹脂からなる凸部２９を設け、また透明電極１８の部分を凹部３０とし、反射部３４のセルギャップが透過部３３よりも狭くなるようにして、外光が液晶層２８を通過する距離を調整している。このような構成の半透過型液晶表示装置は、一般にマルチギャップ半透過型液晶表示装置と呼ばれている。
【００１０】
【発明が解決しようとする課題】
近年では、セルギャップを規定するためのスペーサとして、従来の球状スペーサよりもセルギャップの制御が容易であり、また光漏れ等のない均一な表示品位が得られる等の理由により、柱状スペーサ２７をアレイ基板上に設けることが主流となりつつある。この場合、パネル全体でのセルギャップを均一にするために、表示領域３１だけでなく、額縁領域３２にも柱状スペーサ２７を配置している。
【００１１】
アレイ基板１０上に柱状スペーサ２７を設ける場合、その密着密度を保つために樹脂層の上に形成する必要がある。表示領域３１内では、図５に示すように、画素の開口率に影響を与えないように補助容量線１７の上に形成されるのが一般的である。したがって、補助容量線１７上には、全面に凸部が設けられ、その上に柱状スペーサ２７が形成されている。同様に、額縁領域３２にも土台となる樹脂層が形成され、その上にセルギャップを均一にする目的で柱状スペーサ２７が形成される。
【００１２】
柱状スペーサ２７となる樹脂層は、樹脂レジスト塗布、露光、現像、剥離の工程を経て形成される。このうち、レジスト塗布において、塗布面の凹凸はその塗布膜厚に大きく影響する。凹凸のある部分は、凹部の存在により塗布面が平坦な場合に比べて膜厚が薄くなるレベリングと呼ばれる現象がおこる。額縁領域３２は凹凸がなく平坦であるが、表示領域３１内には透過部３３と反射部３４とにより凹凸が存在するためレベリングが発生する。このため、表示領域３１ではレベリングにより、額縁領域３２と比較してレジストの塗布膜厚が薄くなり、表示領域３１と額縁領域３２とでは柱状スペーサの高さに違いが生じる。そして、このようなセルギャップ不良により、表示品位が低下するという不具合が生じていた。
【００１３】
本発明の目的は、柱状スペーサの高さの違いに起因するセルギャップ不良をなくし、良好な表示品位を得ることができる液晶表示装置を提供することにある。
【００１４】
【課題を解決するための手段】
上記課題を解決するため、請求項１の発明は、外光を反射して画像を表示する反射部と、バックライト光を透過して画像を表示する透過部とを有する画素電極が表示領域内に規則的に配置された第１の電極基板と、前記画素電極と相対する対向電極が全面に形成された第２の電極基板と、前記第１の電極基板の反射部に形成された凸部と、前記第１の電極基板の透過部に形成された凹部と、前記反射部に形成された凸部上に配置され前記第１及び第２の電極基板間の間隔を規定する、樹脂レジスト工程を経て形成された複数の柱状スペーサと、前記複数のスペーサにより間隔が規定された前記第１及び第２の電極基板間に充填された液晶層とを備える液晶表示装置において、前記表示領域外側の額縁領域に、前記画素電極の前記反射部に形成された凸部と同等の凸部、及び前記透過部に形成された凹部と同等の凹部がそれぞれ形成され、前記額縁領域に形成された凸部上に前記柱状スペーサが配置されていることを特徴とする。
【００１５】
請求項２の発明は、請求項１において、前記額縁領域に形成された凹部の開口面積が前記透過部に形成された凹部の開口面積よりも広いことを特徴とする。
【００１６】
好ましい形態として、前記額縁領域において、前記表示領域に近い部分にある凹部の開口面積を、前記表示領域の凹部の開口面積Ｓ１と同等とし、前記表示領域から離れるに従い、凹部の開口面積Ｓ２を徐々に広くする。
【００１７】
請求項３の発明は、請求項１又は２において、前記額縁領域に形成された凹部に、スペーサとして機能しない突起が配置されていることを特徴とする。
【００２０】
【発明の実施の形態】
以下、本発明に係わる液晶表示装置の実施形態を添付の図面を参照しながら説明する。
【００２１】
なお、本実施形態の説明で用いる概略断面図は図６に対応しているが、内部の構成は適宜省略している。
【００２２】
図１は、第１の実施形態に係わる液晶表示装置の概略断面図である。この実施形態では、額縁領域３２において、表示領域３１の反射部３４に形成された凸部２９と同等の凸部３６が形成されると共に、同じく表示領域３１の透過部３３に形成された凹部３０と同等の凹部３７が形成されている。図１に対応する概略平面図を図２に示す。ただし、図２と図１では、表示領域３１と額縁領域３２の位置、及び凹部３７の配置等が異なる。
【００２３】
額縁領域３２に形成される凸部３６と凹部３７は、表示領域３１の凸部２９及び凹部３０と同一のプロセスで形成することができる。また、額縁領域３２の柱状スペーサ３８は、凸部３６の上に配置されている。
【００２４】
上記構成によれば、額縁領域３２に凸部３６と凹部３７とが形成されているため、レジスト塗布により柱状スペーサ２７，３８を形成した際に、額縁領域３２のレジスト膜厚にもレベリングが生じる。すなわち、図１の破線３９で示すように、柱状スペーサ２７，３８のレジスト塗布面は表示領域３１も額縁領域３２もほぼ等しい凹凸が生じることになるため、このレジストにより形成される柱状スペーサ２７，３８の高さもほぼ等しくなる。したがって、アレイ基板と対向基板とを貼り合わせた際に、柱状スペーサ２７，３８の高さの違いによるセルギャップ不良を生じることがなく、良好な表示品位を得ることができる。
【００２５】
図３は、第２の実施形態に係わる液晶表示装置の概略断面図である。この実施形態では、額縁領域３２に形成した凹部３７の開口面積Ｓ２が、表示領域３１に形成した凹部３０の開口面積Ｓ１よりも広くなるように構成されている。その他の構成は図１と同じであり、同等部分を同一符号で示している。
【００２６】
上記構成によれば、レジスト塗布により柱状スペーサ２７，３８を形成した際に、表示領域３１のレジスト膜厚よりも、額縁領域３２のレジスト膜厚の方により大きくレベリングが生じる。すなわち、図２の破線３９で示すように、柱状スペーサ２７，３８のレジスト塗布面は表示領域３１よりも額縁領域３２の方が凹み大きくなるため、このレジストにより形成される柱状スペーサ３８の高さは、柱状スペーサ２７よりも低くなる。
【００２７】
通常、アレイ基板と対向基板との貼り合わせにおいて、両基板に挟まれた柱状スペーサは、その上部がわずかに潰れ、パネル全体でほぼ均一なセルギャップとなる。しかし、柱状スペーサ３８の潰れは、基板周囲を被っているシール材３５の影響を受けやすく、シール材３５に近いほど潰れにくくなる。このため、柱状スペーサ２７，３８をほぼ同一の高さに形成したとしても、基板を貼り合わせた後では、表示領域３１の柱状スペーサ２７よりも、額縁領域３２の柱状スペーサ３８の方が高くなり、セルギャップ不良を生じることがある。
【００２８】
これに対し第２の実施形態では、レジスト塗布面の凹みが、表示領域３１よりも額縁領域３２の方が大きいため、基板を貼り合わせた際に、額縁領域３２の柱状スペーサ３８はシール材３５の影響を受けにくくなり、貼り合わせ後のセルギャップをパネル全体でほぼ均一にすることができる。したがって、セルギャップ不良を生じることがなく、良好な表示品位を得ることができる。
【００２９】
なお、柱状スペーサ３８はシール材３５に近づくにつれて潰れにくくなるため、額縁領域３２において、表示領域３１に近い部分にある凹部３７の開口面積Ｓ２を、表示領域３１の凹部３０の開口面積Ｓ１と同等とし、表示領域３１から離れるに従い凹部３７の開口面積Ｓ２を徐々に広くしてもよい。これにより、額縁領域３２に配置される柱状スペーサ３８のうち、表示領域３１に近い部分に形成される柱状スペーサ３８は表示領域３１の柱状スペーサ２７と同等の高さとなり、シール材３５に近くなるにつれて、柱状スペーサ３８の高さが徐々に低くなるようにすることができる。このような構成とすることにより、貼り合わせ後のセルギャップをパネル全体でより均一なものとすることができる。
【００３０】
図４は、第３の実施形態に係わる液晶表示装置の概略断面図である。この実施形態では、額縁領域３２に形成した凹部３７に、図示しない対向基板と接触することがなく、スペーサとしては機能しない突起４１が配置されている。この額縁領域３２に形成される突起４１は、柱状スペーサ２７，３８と同一のプロセスで形成することができる。その他の構成は図１と同じであり、同等部分を同一符号で示している。
【００３１】
上記構成においても、先の実施形態と同様に、レジストにより形成される柱状スペーサ２７，３８の高さをほぼ等しくすることができるため、アレイ基板と対向基板とを貼り合わせた際に、柱状スペーサ２７，３８の高さの違いによるセルギャップ不良を生じることがなく、良好な表示品位を得ることができる。
【００３２】
更に図３の構成によれば、額縁領域３２の凹部３７に突起４１を配置したことにより、額縁領域３２に配置される図示しないドライバ回路内の配線容量を減らすことができるため、低消費電力化と信号波形の遅延によるドライバ回路の誤動作を解消することができる。
【００３３】
【発明の効果】
以上説明したように、本発明によれば、表示領域と額縁領域における柱状スペーサの高さの違いに起因するセルギャップ不良をなくすことができるので、液晶表示装置として良好な表示品位を得ることができる。
【図面の簡単な説明】
【図１】第１の実施形態に係わる液晶表示装置の概略断面図。
【図２】図１に対応する概略断面図。
【図３】第２の実施形態に係わる液晶表示装置の概略断面図。
【図４】第３の実施形態に係わる液晶表示装置の概略断面図。
【図５】半透過型液晶表示装置の画素構造を示す概略平面図。
【図６】図４のＡ領域に対応する概略断面図。
【符号の説明】
１０…アレイ基板、１１…ガラス基板、１２…信号線、１４…走査線、１６…画素電極、１７…補助容量線、１８…透明電極、１９…反射電極、２２…対向基板、２７，３８…柱状スペーサ、２８…液晶層、２９，３６…凸部、３０，３７…凹部、３３…透過部、３４…反射部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display device having a reflective display region and a transmissive display region in one pixel, and more particularly to a substrate structure on the array side.
[0002]
[Prior art]
In recent years, as a liquid crystal display device assumed to be used outdoors, a transflective liquid crystal display device having a reflective display region (hereinafter referred to as a reflective portion) and a transmissive display region (hereinafter referred to as a transmissive portion) in one pixel is often used. It has been. In this transflective liquid crystal display device, an image is displayed by using a reflection part as external light and a transmission part as backlight light source.
[0003]
FIG. 5 is a schematic plan view showing a pixel structure of the transflective liquid crystal display device, and FIG. 6 is a schematic cross-sectional view corresponding to a region A in FIG.
[0004]
Here, the main components will be described, and the configuration and description of other components will be omitted. Hereinafter, a description will be given with reference to FIGS.
[0005]
The array substrate 10 is composed of a transparent glass substrate 11, and its planar area is divided into a display area 31 and a frame area 32. Among these, in the display region 31, a plurality of scanning lines 14 orthogonal to these are arranged in a matrix via a plurality of signal lines 12 and an interlayer insulating film 13, and a pixel for each lattice (pixel) of this matrix. A pixel TFT 15 and a pixel electrode 16 are formed as a switch element. A storage capacitor line 17 is formed in parallel with the scanning line 14.
[0006]
In each pixel, the transmission part 33 is arranged in the central area of the pixel, and the reflection part 34 is arranged in the peripheral area of the pixel. The pixel electrode 16 is configured as a transparent electrode 18 with an ITO film or the like in the transmission part 33, and is configured as a reflection electrode 19 with a metal film or the like in the reflection part 34. The reason why the transmissive portion 33 is disposed in the central area of the pixel is that there are many opaque wirings such as the signal lines 12 and the scanning lines 14 in the peripheral area of the pixel, which is advantageous in terms of light utilization efficiency. Further, the reflective electrode 19 has irregularities on the surface in order to widen the viewing angle of the reflected light. A polarizing plate 20 and a backlight 21 are arranged on the outer side of the array substrate 10, and an alignment film (not shown) is formed on the inner side so as to cover the surface.
[0007]
On the other hand, the counter substrate 22 is composed of a transparent glass substrate 23 like the array substrate, and a counter electrode 24, a color filter 25, and the like are formed on the surface, and an alignment film (not shown) is formed so as to cover the surface. Is formed. A polarizing plate 26 is disposed outside the counter substrate 22.
[0008]
The array substrate 10 and the counter substrate 22 are opposed to each other at a predetermined interval by columnar spacers 27 that define a cell gap, and are bonded together by a sealing material (not shown) formed so as to surround the periphery of the substrate. A liquid crystal layer 28 is injected between the substrates and filled inside.
[0009]
By the way, in the transflective liquid crystal display device, the path through which light passes through the liquid crystal layer 28 differs between the transmissive part 33 and the reflective part 34. That is, in the transmission part 33, the transmitted light L1 from the backlight 21 passes through the liquid crystal layer 28 only once, whereas in the reflection part 34, external light incident from the counter substrate 22 side passes through the liquid crystal layer 28. The light is reflected by the reflective electrode 19, passes through the liquid crystal layer 28 again, and is extracted as reflected light L2. For this reason, the distance that the reflected light L2 passes through the liquid crystal layer 28 is longer than the transmitted light L1. Therefore, in order to obtain optimal optical characteristics in both reflective display and transmissive display, it is necessary to design each of the reflective portion 33 and the transmissive portion 34 with an optimal cell gap. Therefore, as shown in FIG. 6, a convex portion 29 made of resin is provided in the lower layer of the reflective electrode 19, and the transparent electrode 18 is a concave portion 30 so that the cell gap of the reflective portion 34 is narrower than that of the transmissive portion 33. Thus, the distance that the external light passes through the liquid crystal layer 28 is adjusted. The transflective liquid crystal display device having such a configuration is generally called a multi-gap transflective liquid crystal display device.
[0010]
[Problems to be solved by the invention]
In recent years, as a spacer for defining the cell gap, the columnar spacer 27 is used because the cell gap can be controlled more easily than a conventional spherical spacer and a uniform display quality without light leakage can be obtained. Providing on the array substrate is becoming mainstream. In this case, columnar spacers 27 are arranged not only in the display region 31 but also in the frame region 32 in order to make the cell gap uniform throughout the panel.
[0011]
When the columnar spacers 27 are provided on the array substrate 10, it is necessary to form them on the resin layer in order to maintain the adhesion density. In the display region 31, as shown in FIG. 5, it is generally formed on the auxiliary capacitance line 17 so as not to affect the aperture ratio of the pixel. Therefore, a convex portion is provided on the entire surface of the auxiliary capacitance line 17, and a columnar spacer 27 is formed thereon. Similarly, a resin layer serving as a base is formed also in the frame region 32, and columnar spacers 27 are formed thereon for the purpose of making the cell gap uniform.
[0012]
The resin layer that becomes the columnar spacer 27 is formed through steps of resin resist coating, exposure, development, and peeling. Among these, in resist coating, the unevenness of the coating surface greatly affects the coating film thickness. In the uneven portion, a phenomenon called leveling occurs in which the film thickness becomes thinner than when the coating surface is flat due to the presence of the recess. Although the frame region 32 is flat without unevenness, leveling occurs because the display region 31 has unevenness due to the transmissive portion 33 and the reflective portion 34. For this reason, in the display area 31, the coating thickness of the resist becomes thin compared to the frame area 32 due to leveling, and the height of the columnar spacers differs between the display area 31 and the frame area 32. And the malfunction that display quality fell by such a cell gap defect had arisen.
[0013]
An object of the present invention is to provide a liquid crystal display device capable of eliminating a cell gap defect caused by a difference in height of columnar spacers and obtaining a good display quality.
[0014]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is directed to a pixel electrode having a reflection part that reflects external light and displays an image and a transmission part that transmits backlight and displays an image. A first electrode substrate regularly disposed on the second electrode substrate, a second electrode substrate having a counter electrode opposed to the pixel electrode formed on the entire surface, and a convex portion formed on a reflective portion of the first electrode substrate And a resin resist process that defines a gap between the first electrode substrate and the concave portion formed in the transmissive portion of the first electrode substrate and the convex portion formed in the reflective portion. A liquid crystal display device comprising: a plurality of columnar spacers formed through a plurality of columnar spacers; and a liquid crystal layer filled between the first and second electrode substrates that are defined by the plurality of spacers. Formed in the reflective area of the pixel electrode in the frame area Equivalent convex portion and convex portion, and the formed transparent portion recesses equivalent recesses are respectively formed, characterized in that the columnar spacers on the convex portions formed in the frame region is located And
[0015]
The invention of claim 2 is characterized in that, in claim 1, the opening area of the recess formed in the frame region is larger than the opening area of the recess formed in the transmission part.
[0016]
As a preferred form, in the frame region, the opening area of the recess in the portion close to the display region is made equal to the opening area S1 of the recess of the display region, and the opening area S2 of the recess gradually increases as the distance from the display region increases. Make it wide.
[0017]
According to a third aspect of the present invention, in the first or second aspect, a projection that does not function as a spacer is disposed in the concave portion formed in the frame region .
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a liquid crystal display device according to the present invention will be described below with reference to the accompanying drawings.
[0021]
The schematic cross-sectional view used in the description of the present embodiment corresponds to FIG. 6, but the internal configuration is omitted as appropriate.
[0022]
FIG. 1 is a schematic cross-sectional view of the liquid crystal display device according to the first embodiment. In this embodiment, in the frame region 32, a convex portion 36 equivalent to the convex portion 29 formed in the reflective portion 34 of the display region 31 is formed, and the concave portion 30 is also formed in the transmissive portion 33 of the display region 31. The recessed part 37 equivalent to is formed. A schematic plan view corresponding to FIG. 1 is shown in FIG. However, FIG. 2 and FIG.
[0023]
The convex part 36 and the concave part 37 formed in the frame area 32 can be formed by the same process as the convex part 29 and the concave part 30 of the display area 31. Further, the columnar spacers 38 in the frame region 32 are disposed on the convex portions 36.
[0024]
According to the above configuration, since the convex portion 36 and the concave portion 37 are formed in the frame region 32, leveling occurs in the resist film thickness of the frame region 32 when the columnar spacers 27 and 38 are formed by resist application. . That is, as shown by a broken line 39 in FIG. 1, since the resist coating surface of the columnar spacers 27 and 38 has substantially the same unevenness in both the display region 31 and the frame region 32, the columnar spacers 27, The height of 38 is almost equal. Therefore, when the array substrate and the counter substrate are bonded, a cell gap defect due to the difference in height between the columnar spacers 27 and 38 does not occur, and a good display quality can be obtained.
[0025]
FIG. 3 is a schematic cross-sectional view of the liquid crystal display device according to the second embodiment. In this embodiment, the opening area S2 of the recess 37 formed in the frame region 32 is configured to be larger than the opening area S1 of the recess 30 formed in the display region 31. Other configurations are the same as those in FIG. 1, and equivalent parts are denoted by the same reference numerals.
[0026]
According to the above configuration, when the columnar spacers 27 and 38 are formed by resist application, leveling occurs more greatly in the resist film thickness in the frame region 32 than in the display region 31. That is, as indicated by a broken line 39 in FIG. 2, the resist coating surface of the columnar spacers 27 and 38 is recessed in the frame region 32 rather than the display region 31, and therefore the height of the columnar spacer 38 formed by this resist. Becomes lower than the columnar spacer 27.
[0027]
Normally, in the bonding of the array substrate and the counter substrate, the columnar spacers sandwiched between the two substrates are slightly crushed at the top, resulting in a substantially uniform cell gap throughout the panel. However, the columnar spacer 38 is easily crushed by the sealing material 35 covering the periphery of the substrate. For this reason, even if the columnar spacers 27 and 38 are formed at substantially the same height, the columnar spacer 38 in the frame region 32 is higher than the columnar spacer 27 in the display region 31 after the substrates are bonded together. Cell gap defects may occur.
[0028]
On the other hand, in the second embodiment, the dent of the resist coating surface is larger in the frame area 32 than in the display area 31, so that the columnar spacers 38 in the frame area 32 become the sealing material 35 when the substrates are bonded together. The cell gap after bonding can be made almost uniform throughout the panel. Therefore, a good display quality can be obtained without causing a cell gap defect.
[0029]
Since the columnar spacer 38 is less likely to be crushed as it approaches the seal material 35, the opening area S2 of the recess 37 in the portion near the display area 31 in the frame area 32 is equal to the opening area S1 of the recess 30 in the display area 31. The opening area S2 of the recess 37 may be gradually increased as the distance from the display region 31 increases. As a result, among the columnar spacers 38 arranged in the frame region 32, the columnar spacer 38 formed in a portion close to the display region 31 has the same height as the columnar spacer 27 in the display region 31 and is close to the seal material 35. Accordingly, the height of the columnar spacer 38 can be gradually lowered. By setting it as such a structure, the cell gap after bonding can be made more uniform in the whole panel.
[0030]
FIG. 4 is a schematic cross-sectional view of a liquid crystal display device according to the third embodiment. In this embodiment, a protrusion 41 that does not contact a counter substrate (not shown) and does not function as a spacer is disposed in the recess 37 formed in the frame region 32. The protrusion 41 formed in the frame region 32 can be formed by the same process as the columnar spacers 27 and 38. Other configurations are the same as those in FIG. 1, and equivalent parts are denoted by the same reference numerals.
[0031]
Also in the above configuration, since the columnar spacers 27 and 38 formed of resist can be made substantially equal in height as in the previous embodiment, the columnar spacers are bonded when the array substrate and the counter substrate are bonded together. A cell gap defect due to the difference in height between 27 and 38 does not occur, and a good display quality can be obtained.
[0032]
Further, according to the configuration of FIG. 3, since the projection 41 is arranged in the recess 37 of the frame region 32, the wiring capacity in the driver circuit (not shown) arranged in the frame region 32 can be reduced, so that the power consumption can be reduced. Thus, the malfunction of the driver circuit due to the delay of the signal waveform can be eliminated.
[0033]
【The invention's effect】
As described above, according to the present invention, it is possible to eliminate a cell gap defect caused by a difference in the height of the columnar spacers in the display area and the frame area, so that it is possible to obtain a good display quality as a liquid crystal display device. it can.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a liquid crystal display device according to a first embodiment.
FIG. 2 is a schematic cross-sectional view corresponding to FIG.
FIG. 3 is a schematic cross-sectional view of a liquid crystal display device according to a second embodiment.
FIG. 4 is a schematic sectional view of a liquid crystal display device according to a third embodiment.
FIG. 5 is a schematic plan view showing a pixel structure of a transflective liquid crystal display device.
6 is a schematic cross-sectional view corresponding to a region A in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Array substrate, 11 ... Glass substrate, 12 ... Signal line, 14 ... Scanning line, 16 ... Pixel electrode, 17 ... Auxiliary capacitance line, 18 ... Transparent electrode, 19 ... Reflective electrode, 22 ... Counter substrate, 27, 38 ... Columnar spacer, 28 ... liquid crystal layer, 29, 36 ... convex portion, 30, 37 ... concave portion, 33 ... transmitting portion, 34 ... reflecting portion

Claims (3)

外光を反射して画像を表示する反射部と、バックライト光を透過して画像を表示する透過部とを有する画素電極が表示領域内に規則的に配置された第１の電極基板と、前記画素電極と相対する対向電極が全面に形成された第２の電極基板と、前記第１の電極基板の反射部に形成された凸部と、前記第１の電極基板の透過部に形成された凹部と、前記反射部に形成された凸部上に配置され前記第１及び第２の電極基板間の間隔を規定する、樹脂レジスト塗布工程を経て形成された複数の柱状スペーサと、前記複数のスペーサにより間隔が規定された前記第１及び第２の電極基板間に充填された液晶層とを備える液晶表示装置において、
前記表示領域外側の額縁領域に、前記画素電極の前記反射部に形成された凸部と同等の凸部、及び前記透過部に形成された凹部と同等の凹部がそれぞれ形成され、前記額縁領域に形成された凸部上に前記柱状スペーサが配置されていることを特徴とする液晶表示装置。A first electrode substrate in which pixel electrodes having a reflective portion that reflects external light and displays an image and a transmissive portion that transmits backlight and displays an image are regularly arranged in the display region; A second electrode substrate having a counter electrode facing the pixel electrode formed on the entire surface; a convex portion formed on a reflective portion of the first electrode substrate; and a transmissive portion of the first electrode substrate. A plurality of columnar spacers formed through a resin resist coating process that is disposed on the convex portions formed on the reflecting portion and defines a distance between the first and second electrode substrates , and the plurality of columnar spacers. In a liquid crystal display device comprising a liquid crystal layer filled between the first and second electrode substrates, the interval of which is defined by a spacer of
A convex portion equivalent to the convex portion formed in the reflective portion of the pixel electrode and a concave portion equivalent to the concave portion formed in the transmissive portion are formed in the frame region outside the display region, respectively. A liquid crystal display device , wherein the columnar spacers are disposed on the formed protrusions . 前記額縁領域に形成された凹部の開口面積は、前記透過部に形成された凹部の開口面積よりも広いことを特徴とする請求項１に記載の液晶表示装置。  The liquid crystal display device according to claim 1, wherein an opening area of the recess formed in the frame region is larger than an opening area of the recess formed in the transmission part. 前記額縁領域に形成された凹部に、スペーサとして機能しない突起を配置されていることを特徴とする請求項１又２に記載の液晶表示装置。The liquid crystal display device according to claim 1, wherein a protrusion that does not function as a spacer is disposed in a concave portion formed in the frame region .
JP2002175950A 2002-06-17 2002-06-17 Liquid crystal display Expired - Fee Related JP4047078B2 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
JP2002175950A JP4047078B2 (en) 2002-06-17 2002-06-17 Liquid crystal display
US10/449,193 US6888609B2 (en) 2002-06-17 2003-06-02 Liquid crystal display device
TW092116255A TWI241426B (en) 2002-06-17 2003-06-16 Liquid crystal display device
KR10-2003-0038654A KR100531937B1 (en) 2002-06-17 2003-06-16 Liquid crystal display device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2002175950A JP4047078B2 (en) 2002-06-17 2002-06-17 Liquid crystal display

Publications (2)

Publication Number Publication Date
JP2004020946A JP2004020946A (en) 2004-01-22
JP4047078B2 true JP4047078B2 (en) 2008-02-13

Family

ID=30437000

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2002175950A Expired - Fee Related JP4047078B2 (en) 2002-06-17 2002-06-17 Liquid crystal display

Country Status (4)

Country Link
US (1) US6888609B2 (en)
JP (1) JP4047078B2 (en)
KR (1) KR100531937B1 (en)
TW (1) TWI241426B (en)

Families Citing this family (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100840931B1 (en) * 2002-09-26 2008-06-24 삼성전자주식회사 Liquid crystal display device and method for fabricating thereof
JP4528531B2 (en) * 2004-01-28 2010-08-18 東芝モバイルディスプレイ株式会社 Liquid crystal display
JP2006301451A (en) * 2005-04-22 2006-11-02 Sharp Corp Liquid crystal display device
KR101152131B1 (en) * 2005-07-22 2012-06-15 삼성전자주식회사 Liquid crystal display
KR101224582B1 (en) * 2006-01-16 2013-01-22 삼성디스플레이 주식회사 Liquid crystal display panel and method for fabricating the same
JP2008015061A (en) * 2006-07-04 2008-01-24 Epson Imaging Devices Corp Transflective liquid crystal display panel
JP5288729B2 (en) * 2007-05-23 2013-09-11 株式会社ジャパンディスプレイセントラル Liquid crystal display
JP2008309857A (en) * 2007-06-12 2008-12-25 Toshiba Matsushita Display Technology Co Ltd Liquid crystal display
TWI418902B (en) * 2008-03-24 2013-12-11 Au Optronics Corp Spacer structure of a display panel
TWI427377B (en) * 2008-12-12 2014-02-21 Au Optronics Corp Transflective-type liquid crystal display panel structure
JP2010139953A (en) 2008-12-15 2010-06-24 Hitachi Displays Ltd Liquid crystal display device
JP5572562B2 (en) 2011-01-19 2014-08-13 株式会社ジャパンディスプレイ Liquid crystal display
US9541800B2 (en) * 2014-06-17 2017-01-10 Innolux Corporation Display panel
CN104820317B (en) * 2015-05-26 2018-05-18 京东方科技集团股份有限公司 A kind of display base plate and preparation method thereof and display device
CN109884826A (en) * 2019-03-13 2019-06-14 深圳市华星光电技术有限公司 Display device structure

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW373098B (en) * 1995-09-06 1999-11-01 Toshiba Corp Liquid crystal exposure component and its fabricating method
JPH10307288A (en) * 1997-05-09 1998-11-17 Minolta Co Ltd Liquid crystal element and its manufacturing method
JP3823016B2 (en) * 2000-07-21 2006-09-20 株式会社日立製作所 Liquid crystal display

Also Published As

Publication number Publication date
US6888609B2 (en) 2005-05-03
US20040012751A1 (en) 2004-01-22
KR100531937B1 (en) 2005-11-28
TWI241426B (en) 2005-10-11
TW200407589A (en) 2004-05-16
KR20040002568A (en) 2004-01-07
JP2004020946A (en) 2004-01-22

Similar Documents

Publication Publication Date Title
JP2907137B2 (en) Liquid crystal display
US7576818B2 (en) Liquid crystal display device and electronic apparatus
JP4209636B2 (en) Liquid crystal display
US7570340B2 (en) Transflective LCD device and fabrication method thereof
JP4047078B2 (en) Liquid crystal display
TWI257498B (en) Liquid crystal display device
TWI485494B (en) Liquid crystal panel and liquid crystal display device using the same
US6912027B2 (en) Transflective liquid crystal display device and fabricating method thereof
US20040090574A1 (en) Transflective liquid crystal display with backlight and reflection film
US7463327B2 (en) Liquid crystal display
JP2004085918A (en) Liquid crystal display device, method for manufacturing same, and electronic apparatus
JP3644442B2 (en) Color filter substrate and manufacturing method thereof, liquid crystal display device and manufacturing method thereof, and electronic apparatus
KR20040084968A (en) Liquid crystal display
JP3901172B2 (en) Liquid crystal display device and electronic device
JP4092177B2 (en) Liquid crystal display
JP4196671B2 (en) Liquid crystal display
JP2003084290A (en) Liquid crystal display device
JP4045878B2 (en) Color filter substrate, electro-optical device, and electronic apparatus
US7420633B2 (en) Liquid crystal display having particular irregularity controlling structure
JP4528531B2 (en) Liquid crystal display
KR100975132B1 (en) Liquid crystal display device
KR100909415B1 (en) Semi-transmissive liquid crystal display and manufacturing method thereof
JP2002182192A (en) Color liquid crystal display
KR20090088627A (en) Transflective type liquid crystal display device
KR20020056690A (en) method of fabricating LCD

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20050610

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20070412

A711 Notification of change in applicant

Free format text: JAPANESE INTERMEDIATE CODE: A711

Effective date: 20070502

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20070814

A521 Request for written amendment filed

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20071010

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20071113

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20071121

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20101130

Year of fee payment: 3

R150 Certificate of patent or registration of utility model

Ref document number: 4047078

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150

Free format text: JAPANESE INTERMEDIATE CODE: R150

S533 Written request for registration of change of name

Free format text: JAPANESE INTERMEDIATE CODE: R313533

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20101130

Year of fee payment: 3

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20101130

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111130

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111130

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121130

Year of fee payment: 5

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121130

Year of fee payment: 5

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

S533 Written request for registration of change of name

Free format text: JAPANESE INTERMEDIATE CODE: R313533

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121130

Year of fee payment: 5

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131130

Year of fee payment: 6

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees